(同济大学建筑工程系  上海 200092)

［提要］  关于有粘结预应力FRP筋混凝土梁的抗裂度和裂缝宽度的计算问题，目前我国现行设计规范中尚无相关规定，ACI 4401R—06规范仅给出了非预应力FRP筋混凝土梁的最大裂缝宽度的计算方法。分别应用我国现行《混凝土结构设计规范》(GB50010—2002)和ACI 318—05规范中适用于普通钢筋混凝土构件的抗裂度公式，计算了国内外30根有粘结预应力FRP筋混凝土梁试件的开裂弯矩。按我国《混凝土结构设计规范》计算的开裂弯矩值与试验结果吻合良好。考虑了FRP筋等效、FRP筋的粘结性能以及环氧涂层钢筋等的影响，对我国《混凝土结构设计规范》中有关受弯构件最大裂缝宽度的计算公式进行了修正。基于提出的修正公式和ACI 440.1R—06规范对国内外24根有粘结预应力FRP筋混凝土梁的试验结果进行计算对比。分析结果表明，文中的计算值与试验结果更为吻合。

［关键词］  有粘结预应力FRP筋  混凝土梁  抗裂度  最大裂缝宽度  计算方法

Calculation Methods for Cracking Moments and Crack Width of Concrete Beams Prest

ressed with Bonded FRP Tendons/Authors:Tan Yuan, Xue Weichen, Wang Xiaohui (Tongji University, Shanghai 200092, China)

Abstract:At present, current Chinese design codes have no provisions for calculation of the cracking moments and maximum crack width of concrete beams prestressed with FRP tendons. ACI 440.1R.06 code provides the calculation methods for the non-prestressed cases. The cracking moments of existing thirty specimens are calculated based on current Chinese design code for concrete structures and ACI 31805 code, respectively. The calculation methods for the maximum crack width in current Chinese design code for concrete structures are modified with taking account of the equivalent of FRP tendons, bond behavior of FRP tendons and the influence of epoxy coated steel bars. In addition, the maximum crack width of existing twenty-four specimens is calculated by the modified formulas and the provisions in ACI 440.1R.06.Comparisons show that the calculated values given by the modified formulas agree well with the experimental results.

Keywords:bonded FRP tendon; concrete beam; cracking moment; maximum crack width; calculation method

交通部西部交通建设科技资助项目（200631882244）；国家“十一五”863计划课题（2006AA11Z103）资助项目。